When to plant in Duarte, CA
USDA Zone 10aHere are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Duarte, California — all computed from Duarte's nearest NOAA weather station.
In zone 10a, frost is a minor factor for Duarte — most perennials thrive, and annual vegetables can go out early and stay late.
Frost probability
MT WILSON CBS · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Duarte’s own odds, recorded at MT WILSON CBS.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | Jun 4 | May 15 | Apr 21 | Oct 3 | Oct 30 | Nov 19 |
| 32°F | May 27 | Apr 28 | Mar 31 | Oct 18 | Nov 15 | Dec 9 |
| 28°F | May 10 | Apr 8 | Feb 28 | Nov 5 | Dec 4 | Dec 29 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Duarte, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 18 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Duarte planting FAQ
When is the last spring frost in Duarte, CA?
Duarte's average last spring frost falls near April 28 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.
When is the first fall frost in Duarte, CA?
The first fall frost in Duarte typically arrives around November 15 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Duarte in?
Duarte is in USDA hardiness zone 10a. In zone 10a, winters are mild — many tender perennials overwinter here.
How long is the growing season in Duarte?
Duarte has about 201 frost-free days — a moderate growing season — between the average last spring frost (April 28) and first fall frost (November 15).
When should I plant tomatoes in Duarte?
For Duarte, sow tomatoes indoors about March 3–March 17 and move the seedlings out around May 5, after the last spring frost.
Never miss a window in Duarte
An email when it’s time to start seeds, transplant, and sow — timed to Duarte’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Monrovia · 3 km
- Azusa · 4 km
- Vincent · 7 km
- Citrus · 8 km
- Arcadia · 9 km
- Baldwin Park · 9 km
- Sierra Madre · 9 km
- Glendora · 10 km
Frost dates recorded at MT WILSON CBS, 14 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Duarte, CA — Frost Dates & Zone 10a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00046006. Retrieved from https://blissgarden.com/california/duarte.